Soldering compound.



. BEST AVAILABLE cop FBANCISYE. J. LITOT, WILKINSBURG, PENNSYLVANIA;

soLnERmG COMPOUND.

Specification of Letters latent.

Patented May 8, 1917.

No Drawing. Original application filed March 22, 1915, Serial No. 16,253. Divided and this application filed June 5, 1916.

To all whom it may concern.

lie it known that I, FRANCIS E. J.Lrro'r, a resident of \Vilkinshurg, in the county of .;\ll1'll0ll and State oflonnsylvania, have invented a new and useful Improvement in Soldering Compounds, of which the fol lowing, is a specification.

'lhisinvention relates ton soldering composition for soldering aluminum either to itself or'to other metals. l'l eretoforc it has i been found iniprzmticahle to solder aluminum effectively, that is, so that the soldered joint \vill'witlistainl the ravages of time and changes of tomperatur fand moisture.

The present invention has for its object a soldering composition by means OfWlliCll aluminum parts may he soldered to each other or to other metals, and in which the soldered connection is both strong and duralilo. Itis also an object of the invention 1 to provide a soldering compound which has a sufficiently low melting point to prevent the aluminum pieces being soldered from becoming annealed because of too high heat being required to melt the solder.

In its preferred form the soldering composition consists of an alloy of zinc, lead 1 andtin inrortain definiteproportions. I have discovered that zinc alone forms a good solder for aluminum articles, but its melting point is so high that the ordinary workman IS lialilo to overheat the aluminum,

jnirtioijilarly if it is in the shape of thin sheets, and thus soriously injurc the same. To overcome this 1 alloy nth the ZIHC, lead and tin, and thus reduce the melting point,

i but without destroying the effectiveness of i the solder.

The preferred proportions in which the zinc, tin and lead are-eoinhined to form an effective and durable solder for aluminum are 25 parts of zinc, all) parts of tin, and 55 parts of lead. This composition forms a solder which is very fluid and has a low' melting point and is therefore suitable for soldering aluminum.

At the same time it forms a joint Which-has great on 'durance'under either mechanical strains or weathering. Its melting point is so low Serial No. 101,883.

that danger of injuring the aluminum dnr ing soldering is entirely avoided, even in the hands of an unskilled workman.

The proportions above. given are susceptible of some var'ation withoutali'ecting the .qualities of the solderingcompound, but any material deviation from the propor tions giyen will impair the usefulness of the compound for solderingaluminum. The

enduring qualities of the soldered joint are H I am aware that solders composed of zinc,

lead and tin hivve lJC'Oll used for soldering a number of metals, but have found that a solder compounded from. those elements will not serve as a durable solder for aluminum unless the mgreiihonts are present in :11 proxin'iatoly definite relative proportions.

If desired, "the tin may be supplied in some form of tin alloy. such as phosphor tin, which also serves .to lower the melting point oi the zinc.

This application is a division of my a1.

plication filed March so, 1915, Serial No. 16,953.

What I claim is 1. solderim compound, containing zine, tin and lead, the tin and lead being each not less than the zinc, so as to reduce the melting point of the nine to a safe limit below the heat which'would injure the parts being soldered.

A soldering compound, containing zinc,

of 25 "pants inc, 45 parts tin, and 55 parts lead. V

In testimony whereof, I have hereunto set tin and lead in the approximate proportions. 

